European health regulators for a second time rejected a diet pill developed by Vivus Inc and said the obesity treatment would not be approved there unless the company conducts a large lengthy trial to prove its heart safety, Vivus said on Thursday. The drug, sold in the United States as Qsymia, was approved by U.S. regulators last year. The U.S. Food and Drug Administration also approved another diet pill, Belviq, sold by Arena Pharmaceuticals Inc, making them the first new obesity drugs approved in the United States in more than a decade. Qsymia, which was to be sold in Europe under the brand name Qsiva, was initially rejected by the European Committee for Medicinal Products for Human Use (CHMP) last October. Vivus requested a re-examination of the decision and was turned down again on Thursday.